GAZA CITY, Gaza Strip (CBS News/CBSDC/AP) — Israel bombed five mosques, a sports stadium and the home of the late Hamas military chief in strikes across the Gaza Strip early Tuesday, a Gaza police official said, as the U.N. chief and the U.S. secretary of state launched a high-level effort to end two weeks of deadly fighting.

The air strikes set off huge explosions that turned the night sky over Gaza City orange. The sound of the blasts mixed with the thud of shelling, often just seconds apart, and the pre-dawn call to prayer from mosque loudspeakers.

The unusually intense Israeli strikes came as U.N. Secretary-General Ban Ki-moon and U.S. Secretary of State John Kerry met in Cairo to launch the highest-level push yet to end two weeks of Israel-Hamas hostilities that have claimed at least 570 Palestinian and 29 Israeli lives.

The U.N. has said a majority of the Palestinians killed were civilians, among them dozens of children. In Israel, the army said two more soldiers were killed in clashes with Hamas fighters, bringing the number of troops killed since July 8 to 27. It’s the highest number of Israeli military fatalities for any campaign since the 2006 Lebanon war. Two Israeli civilians have also been killed.

The U.N. Security Council is slated to meet Tuesday morning to take up the Middle East and the Gaza-Israel conflict, reports CBS News’ Pamela Falk. The secretary general is expected to brief the council via video link from Ramallah, the U.N. press office confirms to CBS News.

Israeli media are reporting that an Israeli soldier is missing following a deadly battle in the Gaza Strip. It’s not clear whether the soldier is dead or alive.

The Reuters news agency cites Israel’s Channel 10 News as saying the military believes the man was killed along with six other troops in an attack on an armored vehicle on Sunday.

The army is only saying that it has identified six of the bodies.

A defense official confirmed to The Associated Press that a soldier is missing. The official spoke on Tuesday on condition of anonymity because he was not authorized to discuss the incident with media.

Hamas earlier this week claimed it had captured an Israeli soldier. Israeli officials initially denied the claim.

For Israelis, a captured soldier would be a nightmare scenario in the ongoing Gaza conflict.

Israeli Prime Minister Benjamin Netanyahu said late Monday that “there’s hope” for a cease-fire with Hamas.

“There’s one side that is clearly bent on escalation and there’s one side, Israel, that is defending its people as any country would under similar circumstances,” he told Fox News, adding that this is “the cruelest, most grotesque war that I’ve ever seen.”

Netanyahu said in the interview that some Western countries are tongue-in-cheek when they say they back Israel defending itself from Hamas.

“There are some in the West who tell us, we support Israel’s right to defend itself … as long as you don’t exercise that right,” Netanyahu told Fox News. “Well what else could we do, what would you do … if 80 percent of your people were in bomb shelters?”

Also Monday, the U.S. State Department recommended that U.S. citizens consider putting off non-essential travel to Israel and the West Bank, and repeated its “longstanding strong warning to U.S. citizens against any travel to the Gaza Strip.”

Early Tuesday, Israeli aircraft hit more than 70 targets in the Gaza Strip, including the home of the late leader of Hamas’ military wing, five mosques and a football stadium, said Gaza police spokesman Ayman Batniji.

Batniji said tank shells damaged several houses along the eastern border of the territory and that at least 19 fishing boats were burned by Israeli navy shells fired from the Mediterranean.

The Israeli military says one of the mosques was used to hide a weapons cache and military compound where what it calls “Hamas terrorists” met, and another targeted mosque was used as a rocket storage facility, operations room and gathering point.

Al Jazeera says its offices in Gaza came under fire and were being evacuated Tuesday. The network asserts the offices were targeted on purpose.

Kerry is hoping to get international support as he pushes for a cease-fire, but he acknowledges the differences between Israel and Hamas run very deep and must be addressed in any long-term solution.

“We will work to see if there is some way to not only arrive at a cease-fire of some kind but to get to a discussion about the underlying issues,” Kerry said at the start of the Monday meeting with Ban. “Nothing will be resolved by any cease-fire, temporary or long, without really getting to those issues at some point, and that’s what we need to do.”

The U.S. stepped up calls Monday for a global push to end the fighting as Kerry tried to help broker a cease-fire that would be the third since 2009 between Israel and Hamas militants.

President Barack Obama, meanwhile, is trying a delicate balancing act on the Mideast conflict. Obama on Monday reaffirmed his belief that Israel has the right to defend itself against a barrage of more than 1,500 rockets launched by Hamas, while voicing fresh concern about civilian casualties.

He said Israel’s military assault of Gaza had already done “significant damage” to Hamas’ network of tunnels, safe havens and other infrastructure as he talked of the need for a cease-fire.

“We have serious concerns about the rising number of Palestinian civilian deaths and the loss of Israeli lives,” Obama said in Washington. “And that is why it now has to be our focus and the focus of the international community to bring about a cease-fire that ends the fighting and can stop the deaths of innocent civilians, both in Gaza and in Israel.”

Kerry flew to Cairo on Monday to join diplomatic efforts to resume a truce that last had been agreed to in November 2012. He will urge the militant Palestinian group to accept a cease-fire agreement offered by Egypt that would halt two weeks of fighting that has descended into war.

Upon arriving, Kerry headed almost immediately into the meeting with Ban, where he announced the U.S. will send $47 million in humanitarian aid for tens of thousands of Palestinians who have fled their homes in Gaza to escape the violence.

Kerry’s top aides warned that achieving an immediate and lasting cease-fire would be difficult, but said he hoped to make progress over the next several days to secure at least a temporary pause in the bloodshed.

Ban, speaking to reporters before the meeting with Kerry, said he was disappointed that nine months of U.S.-led talks between Israel and the Palestinians hadn’t yielded better results. Those negotiations broke off last April after it was clear that neither side would make major concessions needed to clinch a peace plan.

“Violence must stop and must stop now,” Ban told reporters.

It’s not clear exactly what Israel and Hamas would each demand in return for agreeing to a truce now, but senior State Department officials said the issue of opening border crossings from Gaza – potentially into Israel and Egypt – was under discussion.

Kerry was expected to meet with Egyptian President Abdel Fattah al-Sisi, Foreign Minister Sameh Shukri, Arab League President Nabil Elaraby and other top officials over the next few days. But there were no immediate plans for face-to-face meetings with officials from Qatar, Turkey, Israel and Ramallah, and the State Department aides said it remained uncertain what could be accomplished in the talks.

A truce between Israel and Hamas has been beset by violence three times since 2009, and was last brokered in November 2012 by Kerry’s predecessor, Hillary Rodham Clinton.

Having already deployed an estimated 1,000 ground troops, Israel’s military has pushed farther into Gaza than it had in 2012 and the conflict is further along now than it was then. At the same time, the State officials noted, Hamas believes it was not given what it was promised in 2012 to lay down its arms, making it more skeptical of a cease-fire now.

Finally, Hamas’ relationship with Egypt, which is negotiating directly with the militant group, has deteriorated since President Mohammed Morsi was ousted in last year’s coup. Egypt has since outlawed Morsi’s party, the Muslim Brotherhood, which has ties to Hamas.

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